At the same way spotify, facebook, whatsapp, instagram show you a notification (popup) when you recive a message, I need to show a message in my app even if this it is off. Any idea?
I guess what you want is push notifications.
Follow this documentation to integrate Azure Notification Hubs in Xamarin:https://docs.microsoft.com/en-us/azure/app-service-mobile/app-service-mobile-xamarin-forms-get-started-push
You can also choose FCM to send the notifications:https://github.com/CrossGeeks/FirebasePushNotificationPlugin
Log in to your account page and head to Notifications settings in the menu on the left to manage your email and push notifications.Note: To receive push notifications, you must allow notifications for the Spotify app in your phone settings.
For me, I use OneSignal
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